Solar System Log by Andrew Wilson, published 1987 by Jane's Publishing Co. Ltd.

The second M-69 spacecraft was identical to its predecessor (launched six days before) and was intended to enter orbit around Mars on 15 September 1969. Like its twin, it never reached intermediate Earth orbit.

During launch, at T+0.02 seconds, one of the six first-stage engines of the Proton exploded. Although the booster lifted off using the remaining five engines, it began veering off course and eventually assumed horizontal attitude, at which point all the remaining first-stage engines shut down. At T+41 seconds, the booster impacted the ground 3 kilometers from the launch site in a massive fireball.

Key Dates

2 Apr 1969: Launch

Status: Unsuccessful

Fast Facts

Second of a new generation of Soviet probes intended to orbit Mars.

This mission was identical to the unsuccessful Mars mission launched in March.

An engine explosion sent the rocket veering off course. It crashed into the ground.